Daniel Hoelbling-Inzko talks about programming

German programming-friendly keyboard layout for Mac OSX

This may sound totally hilarious to people used to the english layout, but german programmers use shortcuts like Shift + 8 to write a [ and ALT-GR + 8 for a {. (Oh and semicolons are only available through shift - yay for C-style languages!) The main reason for this is that we have these useless little umlauts üöä that sit right where the useful keys for a programmer would be, were it not for the german keyboard.

But after years of arm-twisting and cursing you get used to that and develop a reasonable degree of efficiency even with a absolutely unsuitable keyboard layout. Only problem: these shortcuts are radically different on the Mac! (And breaking the built-in keyboard of your Laptop is not really an option as others suggest)

Instead of Shift 8 for a brace it's ALT + 5, and the backslash is skillfully hidden behind ALT+Shift+6 yuck!

So I tried for a few days and then I decided to stop the madness! Instead of learning to use yet another crappy german keyboard layout I started to use the standard english one. And it's awesome, once you get used to it feels absolutely natural, and it also shows that all programming languages have been written to be easy on people with english keyboard layouts.

Only problem: I was severly handicapped when writing german emails to customers or writing german translation texts. I mean, my friends and colleagues can read written out umlauts (ä = au ..) just fine, but it looks totally stupid when writing something official and well phrased and you are misspelling stuff (ß can be sloppily substituted by ss, but there are cases where ss is orthographically wrong and in other cases ß would be wrong and ss right).

So I investigated and found this wonderful Mac program called Ukulele that allows you to write your own keyboard layout files for OSX. I took the standard US layout and altered it to incorporate the german umlaut keys where they are actually printed on the keys, but only if you hit ALT. So ALT + ; turns into a ö etc..

Here a quick overview of the english layout (notice how conveniently located all those symbols are):


And once you hold down ALT:


Since most people I mention this to usually give me a: "wow that's a really good idea" I decided to simply upload the .keylayout file so people don't have to bother with Ukulele themselves.

You can download the keylayout here: US-daniel.keylayout.


Download the file and place it in ~/Library/Keyboard Layouts/, logout and log back into the machine. Now open your System preferences (Sprache & Text) and search for U.S. Tick the checkbox next to it and you can now select the U.S. Keyboard from the OSX menu bar.

Tipp: If you have the screen real estate to share and are still learning the english keyboard layout it's really useful to enable the "Keyboard overview" (Tastaturübersicht anzeigen in german). You can see in real-time what keys are mapped to what buttons on your keyboard while holding down modifier keys.

Filed under osx, programming

GDI Drawing: String with word-wrap

GDI drawing is magic and not very well documented. Finding out how to make GDI draw a string inside a fixed width without constraining the height took me about 20 minutes, hopefully this post saves you 20 minutes of your life nobody will give you back :).

The problem with Graphics.DrawString() is that you can either supply a PointF that will be used as the origin, or you supply a RectangleF as layout rectangle. The rectangle’s sizes and position will be forced upon the text and word-wrap will happen to fit the text inside the rectangle, anything not fitting in the rectangle (given the font-size) will be cut off.
So if you don’t want to confine width or the height, setting that property on the RectangleF to 0 will make GDI not "cut off” but expand the rectangle as needed.

Needless to say that this behavior isn’t mentioned on the MSDN page for DrawString, that may have saved me time.

You have to know English to be a Programmer!

Scott Hanselman just blogged this interesting letter from Fabrice Fonck on Microsoft’s effort to localize Visual Studio and .NET entitled Do you have to know English to be a Programmer? and I wanted to share my thoughts on this as a non-native speaker:

As most of you may know, I am from Austria – so my native tongue is German. There should be about 100 million people speaking that language and so it’s rather natural that there are many sites discussing programming topics in German and also there are many books that get translated. So, while I know that you could be a rather successful programmer in Germany/Austria without English, I really believe it’s utterly impossible to be a good programmer without being fluent in English!

Why? Simply, because being a good programmer is not about knowledge, ability or technology but about your ability to acquire even more knowledge and constantly improve and refine your skills.

And you really can’t do that if deny yourself access to 90% of the internet’s resources. You’ll miss out on great articles from people like Scott Hanselman, Ayende Rahien, Miško Hevery, Rob Conery, Carl Senguin and many more who have contributed great articles that have influenced my skill directly.

Not accepting that English is the predominant language in software development only fragments the community and hinders sharing of knowledge.

And to be honest, all our programming languages are based on the English syntax, so I can’t think about a way for somebody with no English skills to write code against the .NET framework anyway. The code we produce is in English and defines it’s context/meaning/purpose through naming. Not being able to understand the meaning of System.Net.MailMessage.To is a serious problem when trying to write software (when not copying snippets and samples).

One thing remains to be said: When writing code I constantly encounter one problem: German speaking customers vs English speaking code. Naming my objects in German doesn't work for me, it starts to feel wrong if you mix two languages (English syntax and German variables), so I translate the German requirements and object names to English ones.

This makes it sometimes difficult to talk to the the customer during development, because I use words he doesn’t know and I constantly have to map his words to mine. This isn’t so much of a problem as long as you as a developer don’t mix things up and choose your translations right. Still it annoys a bit and I would be thankful for a English customer once in a while :).

Finally: I switched my blog to English almost a year ago because I felt that blogging in German created a barrier for me. I couldn’t point anyone outside Austria/Germany to my writings. And while many people since have asked my why I neglect German (mostly out of curiosity), I can’t say I have ever regretted this move (and my English did benefit from this).

Patience is a virtue I don’t have

I hate waiting for stuff when working. Whenever something hangs, lags or simply doesn’t work right the first time I get annoyed.

Usually a little distraction like this doesn’t really hurt too much, but when you are deep in thought while programming – and something hangs, I can almost feel how my memory gets flushed and my productivity drops to zero for the next few minutes while I try to get back into everything.

This is very very very bad, and that’s why I am feeding insane amounts of money to the hardware vendors. I need the best performance not because of the insane calculations I do but simply because I can’t afford to get distracted by lagging applications.

Same thing applies to unit tests and build processes. It’s important to keep those as short as possible. If I’m doomed to wait for 2 minutes to see if my unit tests pass or not I will either not run them as frequently, or I will run them and do something else in between. Either way I loose productivity.

So, while at it, I guess the server I wanted to configure stopped hanging while I wrote this.

Anatomy of a pattern: Singleton

Singleton is one of the simplest patterns that does just one thing: Ensure that there is one object to rule them all, one object to bind... (Ok sorry got dragged away).

The idea is simple: Sometimes (especially when writing to disk with open file handles) you need to ensure that there is only ONE instance of a class going on at any time. And that's it. It's so simple, you could turn it into a 1-liner:

public static Singleton _Instance;

But things never are that simple ;). By using only a shared variable you may end up calling the constructor twice, resulting in 2 objects that may get used by two different clients.

To avoid this you'll need to get an exclusive lock of the Singleton to ensure it's really empty before you instance it.
And that's how it's usually done

private static Singleton _Instance;
private static Object __LockObject = new object();

public static Singleton GetInstance() {     if (_Instance == null)     {         lock(__LockObject)         {             if (_Instance == null)                 _Instance = new Singleton();         }     }     return _Instance; }

In the singleton implementation the static Singleton variable holds the reference to the Singleton, and whenever we try to get a reference to this instance we check if it's already set and return the value.

If not, it get's tricky when 2 threads are getting a cache-miss at the exact same time (_Instance == null). If you aren't synchronizing at this point you may end up with two different references of a singleton object being used (and causing problems with resources being consumed twice, causing ). So it's important to perform another check when you have exclusive reign over the shared object (by using a lock object here).

This ensures that no two threads will try to create a new instance to your singleton, while not slowing down your read-performance at all.

Sample code: Singleton.cs

Computer Programming Quotes

Oh god, I am still laughing after having read this brilliant list of 101 Great Computer Programming Quotes I found on DotNetKicks.

Here are some of my favorites, although I would recommend the whole list to anyone with some spare time!

  1. “Saying that Java is nice because it works on all OSes is like saying that anal sex is nice because it works on all genders.”
  2. “Computers are like bikinis. They save people a lot of guesswork.”
    (Sam Ewing)
  3. “Programming is like sex: one mistake and you’re providing support for a lifetime.”
    (Michael Sinz)
  4. “Programmers are in a race with the Universe to create bigger and better idiot-proof programs, while the Universe is trying to create bigger and better idiots.  So far the Universe is winning.”
    (Rich Cook)
  5. “It’s ridiculous to live 100 years and only be able to remember 30 million bytes.  You know, less than a compact disc.  The human condition is really becoming more obsolete every minute.”
    (Marvin Minsky)
  6. “Hardware: The parts of a computer system that can be kicked.”
    (Jeff Pesis)
  7. “I’ve finally learned what ‘upward compatible’ means.  It means we get to keep all our old mistakes.”
    (Dennie van Tassel)
  8. “There are two major products that come out of Berkeley: LSD and UNIX.  We don’t believe this to be a coincidence.”
    (Jeremy S. Anderson)
  9. “There are two ways of constructing a software design.  One way is to make it so simple that there are obviously no deficiencies. And the other way is to make it so complicated that there are no obvious deficiencies.”
    (C.A.R. Hoare)
  10. “Software suppliers are trying to make their software packages more ‘user-friendly’…  Their best approach so far has been to take all the old brochures and stamp the words ‘user-friendly’ on the cover.”
    (Bill Gates)
  11. “There’s an old story about the person who wished his computer were as easy to use as his telephone.  That wish has come true, since I no longer know how to use my telephone.”
    (Bjarne Stroustrup)
  12. “The use of COBOL cripples the mind; its teaching should therefore be regarded as a criminal offense.”
    (E.W. Dijkstra)
  13. “There is no programming language–no matter how structured–that will prevent programmers from making bad programs.”
    (Larry Flon)

Enumerators in C#

I am still trying to figure out if what I did was useful or not.

Based on the assumption that sometimes you may need a variable typed IEnumerable<T> to hold a value that only implements IEnumerable I wrote this adapter class (you find it after the jump).

What's IEnumerator?
IEnumerator it the old non-generic implementation of the Iterator pattern, while IEnumerator<T> is the strongly-typed generic version introduced in .NET 2.0.

IEnumerable<T> implements IEnumerable, but there is no way to cast IEnumerable to IEnumerable<T>. So I wondered how you could comply to the Iterator pattern.

My first suspicion came when I tried foreach on both IEnumerables. Foreach has no problem with both of them, so I dug out my C# language spec and discovered that foreach has to use two different methods for either IEnumerable or IEnumerable<T> (That's not really clear there, anyone to falsify my assumption?).
They could have gone the other way and use the non-generic IEnumerable for the iteration, but that would need an implicit typecast on every iteration (and that would slow things down I guess).

In a scenario like the following one you can't pass the Enumerator created by an Array.GetEnumerator() because it uses IEnumerator instead of the generic version IEnumerator<T>.

public void PrintList(IEnumerable<String> MyList)
foreach (String Entryin MyList)
Console.WriteLine("{0}", Entry);

Because IEnumerable<T> implements IEnumerable you could just switch back to the non-generic version, but that's something I don't really like (although it may be more practical).

So here are 2 (very simple) adapter classes that will provide upward-compatibility to your IEnumerable and IEnumerator needs:

public class GenericEnumerableAdapter<T> : IEnumerable<T>
    private IEnumerable _Old;
    public GenericEnumerableAdapter(IEnumerable OldEnumerable)
        this._Old = OldEnumerable;

#region IEnumerable<T> Members

public IEnumerator<T> GetEnumerator() { return new GenericEnumeratorAdapter<T>(_Old.GetEnumerator()); }


#region IEnumerable Members

IEnumerator IEnumerable.GetEnumerator() { return _Old.GetEnumerator(); }

#endregion }

public class GenericEnumeratorAdapter<T> : IEnumerator<T> { private IEnumerator _OldEnum; public GenericEnumeratorAdapter(IEnumerator OldEnumerator) { _OldEnum = OldEnumerator; }

#region IDisposable Members

public void Dispose() { this._OldEnum = null; }


#region IEnumerator<T> Members

public T Current { get { return (T)_OldEnum.Current; } }

object IEnumerator.Current { get { return _OldEnum.Current; } }

public bool MoveNext() { return _OldEnum.MoveNext(); }

public void Reset() { _OldEnum.Reset(); }

#endregion }

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